The old mental image we have of dinosaurs as huge, slow, stupid beasts is wrong, too. For one thing, they weren't all huge. Even full-grown dinosaurs came in varieties as small as chihuahuas. Plenty of them were people-sized. Some were the largest land animals ever, true, but of those none came close to our fellow mammal, the blue whale. Were those giants slow? The largest mammals -- elephants, hippos, rhinos -- can run faster than you can. There's no reason to think that even the behemoth Seismosaurus couldn't move right along when he wanted to. And there's plenty of evidence that many of the carnivores were outright roadrunners. The same applies to stupid: some more, some less -- like us. Certainly, none had people-smarts, and probably none reached the level of our fellow primates. But we know that some were speedy pack hunters, preying on organized herds of much larger animals, like modern wolves -- and wolves are pretty smart.
Some misconceptions about dinosaurs have already faded out. Even little kids no longer envision hairy cavemen being chased by allosaurs, or riding tamed brontosaurs. They know that the last dinosaurs were gone long, long before the first humans (unless their "knowledge" of prehistory comes from Kent Hovind or others of that ilk). But some qualities of dinosaurs are still being worked out by paleontologists. We are discovering, for example, that some -- maybe most -- dinosaurs had societies: they lived in families, herds, or packs. And that means leaders, followers, rules of conduct, and social duties to perform. They weren't just big, stupid individuals looking out only for themselves. Even their most reptile-like quality -- cold-bloodedness -- is being challenged. Some very knowledgeable people are offering some very convincing proof that at least some dinosaurs were warm-blooded.
But we can surely rest comfortably in one piece of knowledge about dinosaurs: they are extinct. And that certainly makes us feel superior, doesn't it? Think again. Dinosaurs were the dominant beasts on earth -- on land, in the sea, and in the air -- for 170 million years. We humans, who like to think that we now rule the Earth, have only been around for two million years or so. If you subtract our lifetime as a species from theirs (as an order), they still dominated the Earth about 170 million years longer than we have. And they didn't die out because our superior (mammalian) kind took over. Our ancestors lived all throughout the dinosaur era -- as tiny, mouselike creatures, eating worms and sucking eggs: sort of in the unnoticed niches of the great dinosaur ecology. But they did become extinct, right? Not if by "extinct" you mean "left no surviving descendants." It has become well established in recent years that modern birds are direct descendants, via Archaeopteryx and other ancestors, of small, carnivorous dinosaurs (not the flying pterosaurs). The research these days is on just which branch of the dinosaur family tree birds took off from. But all the rest of the dinosaurs certainly did become extinct, and we haven't figured out exactly why yet -- perhaps some disastrous combination of climate change and an asteroid crash or two. But one thing we can be certain of is that dinosaurs did not purposely or carelessly destroy their own world. So far humans are the only animals that have ever provided themselves with the ability to do that.
So not all dinosaurs were big, stupid, slow brutes. Some were small, fast, and probably warm-blooded. They were entirely successful, for great, long ages in their world. Whatever wiped them out, it wasn't their own inefficiency, and because there was nothing to take their places in the ecosystem for millions of years, until mammals, freed from the domination of the great reptiles, diversified and claimed the world. And -- remember -- some of them are still here, raising their warm-blooded, feathered, but still scaly-legged young, generation after generation.